If an umpire wears a non-approved shirt during a game, what is the ruling?

The ruling requires that the umpire must wear an identical, approved uniform to ensure consistency and professionalism on the field. Official uniforms are established to create a standard look for officials, which helps maintain the integrity of the game. It is important for all umpires to be easily recognizable and represent the governing body of the sport appropriately, which is facilitated by the use of approved uniforms. Allowing any variation in attire could cause confusion among players, coaches, and spectators, undermining the authority of the officiating crew. Uniform standards also help in establishing respect for the game and its officials.